Method of cleaning internalcombustion engines



Patented Mar. 2, 1954 UNITED STATES PATENT OFFICE METHOD OF CLEANING INTERNAL- COMIBUSTION ENGINES poration of Ohio No Drawing. Application November 1, 1948, Serial No. 57,823

2 Claims. (01. 134-20) The present invention relates to an internal engine cleaning composition. It is a liquid mixture in the form of a clear, transparent, colloidal suspension comprising a phenol, soap and hidrocarbon oil as its essential components. The invention also relates to a method of cleaning internal combustion engines and engine parts with the new composition.

One object of the invention is to provide a cleaning composition that is easy and safe to handle and has the ability to thoroughly cleanse the interior of an engine by removing varnish, sludge and other foreign materials that may be deposited, caked or otherwise affixed in or to the parts or small spaces thereof without requiring the engine to be taken apart.

It has been found that a composition obtained by combining one or more phenols, soap and a hydrocarbon oil has surprisingly excellent cleansing qualities and that when used in accordance with the method of this invention, this composition is capable of restoring the interior of an internal combustion engine to a factory clean condition Without harmful effects to the engine.

The soap component is one or more alkali metal salts of the higher unsaturated fatty acids preferably having saponification values not greater than about 205 and iodine values not less than about 75. The soap component may be added to the mixture as such or be formed in situ by saponifying, with an alkali metal hydroxid such as potassium hydroxide, sodium hydroxide or a mixture thereof, vegetable or animal oils, such as cottonseed, corn, soybean, tung, linseed, olive, castor, peanut, seal or whale blubber oil.

The phenol component may be unsubstituted phenol, an alkyl substituted phenol such as a cresol, ethyl phenol, xylenol or mesitol, or a com--* bination thereof. For the purposes of this invention, cresols consisting predominantly or solely of ortho-cresol are preferred for the reason that cleaning compositions containing such a cresol have been found to be up to three times as effective as compositions containing a mixture of ortho-, metaand para-cresol, such as is ordinarily used from coal tar.

The hydrocarbon oil component may be kero- I lubricate the parts thereof.

2 to form a solution of phenol and soap and then to add the hydrocarbon oil.

Another method, when the oap is not available as such, is to dissolve one or more vegetable or animal oils having a saponification value not greater than about 205 and iodine value not less than about in a solvent, such as alcohol, saponifying the oil with a stoichiometric amount of an aqueous solution of alkali metal hydroxide, then adding the phenol to form a phenol-soap solution and finally adding the said solution to the hydrocarbon oil.

Still another method is to mix the phenol with one or more of the vegetable or animal oils, saponifying the oil or oils in situ by adding the aqueou solution of an alkali metal hydroxide and heating the mixture while stirring and, when the saponification is completed, adding the hydrocarbon oil to form the final composition.

In either of the later two methods, the completion of the sapom'fication of the oil will be indicated by the fact that a small portion thereof will form a clear solution with hot distilled water.

The ratio of phenol to soap may vary widely and is determined largely by the miscibility .of the phenol-soap solution with the hydrocarbon oil. Ordinarily, the proportion of phenol should be at least suflicient to make the phenol-soap solution miscible with oil. If the proportion of phenol is appreciably less than about equal to the amount of soap, the solution will become immiscible with the oil. There is no critical upper limit to the amount of phenol in the soap solution. The relative proportions of phenol to soap may be as high as 2 or '3 to It is preferred that the amount of the alkali metal hydroxide be not substantially more than that needed to form the soap, but since the amount is not critical, small amounts of the alkali metal cresolate may be formed and do not interfere with the utility of the composition.

The amount of phenol-soap solution in the cleaning composition may likewise vary within a wide range. Since the composition is preferably used in an engine while the engine is running, it is essential that at least some oil be present to Test have shown that very satisfactory results are obtained when the phenol-soap component is present to the extent of as little as 25% and as high as The cleansing effect increases with an increase in the proportion of phenol-soap component and superior results are obtainable when the phenolsoap component is present in proportions as high as 90%.

For practicable purposes, the range of concentration of the phenol-soap component in the composition may, therefore, vary between about 25% and 90%. For reasons of economy, however, it is preferable to keep the concentration of the phenol-soap component in th vicinity of 25% to,5.0%.

The preferred cleaning composition therefore is one wherein the proportions of phenol, soap and hydrocarbon oil are about 12.5:12.5:75 to 25:25:50. One such composition is readily obtained by adding 25 parts of liquor cresolisfsapo natus, wherein the phenol is orthocresol and the saponified oil is linseed oil, to 25. to, 25 parts. hydrocarbon oil. V

In accordance with the method of this invention, the crankcase oil of a dirty engine isdrained and replaced by an equal or greatervolunie, oi"

the cleansing composition. The engine is then the. cleaning composition but not carried corn-.

pletely out offthe crankcase.

The following examples are included to further illustrate. the present invention.

A conventional Chevrolet engine having a, pis tondisplacernent of 216.5 cu. in. and a compres- Sign, ratio of. 6.1:]. and containing in the crank: case an S. A. E. 30 grade lubricating oil, having added thereto iron naphthenate as an oxidation catalyst, was run for- Z l hours at 3150B. 1?. M. with a load of- 30 B. H. 1?. The temperature of the cooling water. at the jacket outlet was 200 F. and the oil temperature was maintained at 280 F. At the end of this run, the engine was cornp letel-y sludged and varnished. The. sludge con-, tent of, the oil had reached up to 8%., the piston den erit rating was 9.0 to 10.0 and the. engine pans and interior. were covered. with a heavy varnish and sludge coating. The cam followers were so badly varnished that they seized in the block, bending the push rods. Severe pounding with a heavy hammer and; punch was necessary toireethese followers. in their guides. Thus, it is, obvious. that the. engine was in a maximum sludged condition.

The oil was, drained from. they dirty, engine. and

fiye .quarts of the preferred cleaning composition of thisinvention were poured into the crankcase. composition consisted oi 75% straw parafiin oilhaving' a viscosity of 75 SUS at 100 and 25 of a 'cresol-soap solution made by dissolving; 5. Par s. volume f in e i -5 arts ethanol and adding thereto a hot solution or tsh We ht of P tas m r xide dis.- solved in parts water while vigorously stirring the mixture. When saponification was corn; pleted. a soap solution having a pH of'8.5 to 9.0 was formed. To this solution there were added- 50 parts by volurne of ortho-cresol.

The engine was then idled for 30 minutes at 2800-11. P. M., the crankcase temperatureb eing maintained between 150 and 160F. At the end; of that tinie, the crankcase was drained, another five quarts of the same cleaning composition e d eed. ine s r n for heddiwas ai-wesu d t e. ame nditio swa hn..( d agai irs uafrtsei. ubr atin wa ead ed an he n:

gine run for another 15 minutes. The oil was then drained and the engine was dismantled.

The dismantled engine was rated by visual inspection of the various parts for sludge and varnish deposits in accordance with an arbitrary system ot demerits In accordance with this systern, a rating of 0,0 is perfect, while 1Q. 0 is the lowest rating obtainable. In Table 1 below there are tabulated the ratings of the engine before and after cleaning in accordance with this example- Table 1 Before After Cleaning Cleaning Piston Skirt Varnish, 0. 0:10. 0 0. 0 Rings and Grooves .Q 2; 0 2 0;

The cleaning of the rocker arms andsi de pan is of necessity less effective than that of the. crankcase parts because the flow is more restricted in those areas. The cleaning procedure removed alltraces of sludge and varnish froin the crankshaft and crankcase surfaces, leaving these important parts in a factory clean condi: tion. Furthermore, all varnish was removedfro n the piston skirts and piston interiors, as well as frojnl the earn followers.

EXAMLLEE A cleaning composition, prepared by combining 100 parts of liquor-cresolis saponatus, eontain-ing as its essential components cresol and saponifiedlinseed oil, the cresolbeingpresent to the extent of= 50:.parts, With 0 partsof straw paraffin oil havinga viscosity of 75* SUS at 1-00 Ffwasused to clean; the engine of a Ghev-rolet; station wagon which hadbecomesludged during-- duty-on the road. Prior to; the cleansing; operatipn, the oil: filtercartridge was removed with considerable effort and the oil filter well was found, upon inspection, to: have accumulated sludge to'a depth of about twoin ches. This is indicative of the completely sludged; and extremely poor condition of the engine.

The enginewascleanedby draining the crankcase, pouring in two gallons of the cleaning composition described in this example and idld the engine for minutes. The crankcase was then drained. and the engine dismantled-for inspection of parts. Itwas foundthat the sludge had-been removed from the parts it had covered before cleaning and that the crankcase was free. trom sludge and varnish.

EXAMPLE, 3.

Thedirtyengine. at a General Motorstruck was, c ned ththe am ompositi n nd: unde the. on itions. as; d salted Example the. dlin ime w th. the clean n q mn sition s. he c an Af case was drained, a hydrocarbon g g 3 hereb leased-1N0.- w ighte asell; 1?. by umeo ker en o i dint he. Gree s as a d; t e e i e as. s dl s. a ab ut.

ni iat s. r m v th du l eanin awepoitiq m. he. en ineaad t arr ou c he;

ca e ns l b e materia w ich; s been.

ssened' dur ng. he c e nine. pmsedure.

Th mp ese qn p un s 9. square n est he ec iwslu l winde s. w s mea u ed siq et i cleaning operation and after the final flushing by removing the spark plugs, putting pressure gauges in the spark plug sockets and turning the engine over with the starter. The ratings ob- It is believed that the beneficial results obtained in this test were due primarily to the freeing of the piston rings and valves and to the cleaning of the valve seats. Inasmuch as the distribution of work among the cylinders is roughly proportional to the compression levels, it is manifest that the equalization of the compression levels resulting from the cleaning operation herein described resulted in a much smoother and more efilcient operation of the engine.

After the compression tests were completed, the engine was dismantled, the interior was found to be perfectly clean, the crankcase was free of varnish and the sludge and the oil screen was open and clean.

It is to be understood, of course, that the composition and method of this invention are susceptible to innumerable modifications that will readily become apparent to those skilled in the art upon reading this description. Thus, while the invention ha been described particularly with reference to compositions containing one or more phenols, related compounds such as naphthols and anthrols, e. g., anthranol, may be used in place of or in addition to a phenol Furthermore, there may be added to the cleaning composition such materials as wetting agents or other detergents. If desired, the temperature during the cleaning operation may be maintained between about 150 F. and a temperature slightly below the boiling point of the cleaning composition. All such modifications are intended to be ing essentially of about 50 to about parts by volume of a hydrocarbon lubricating oil having a viscosity ranging from about 75 SUS at F. up to SAE 30 to 50 to 25 parts by volume of a cresolsoap solution, said solution comprising about equal parts by volume of ortho-cresol and of a potassium linseed oil soap solution, said soap solution having a pH between about 8.5 and 9.0, idling the engine for a period up to about one hour and thereafter draining the engine.

2. A method of cleaning an engine internally which comprise introducing into the crankcase of the engine an amount of a cleaning composition at least equal to the lubricating oil capacity of the engine, said cleaning composition consisting essentially of about 50 to about 75 parts by volume of a hydrocarbon lubricating oil having a viscosity ranging from about 75 SUS at 100 F. up to SAE 30 to 50 to 25 parts by volume of a cresolsoap solution, said solution comprising about equal parts by volume of ortho-cresol and of a soap solution, said soap solution having a. pH between about 8.5 and 9.0 and the soap in said soap solution being a soap selected from the group consisting of the potassium and sodium soaps of an oil selected from the group consisting of linseed, soy bean and corn oil, idling the engine for a period up to about one hour and thereafter draining the engine. I

KARL H. OBERMEIT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,032,174 Johnson Feb. 25, 1936 2,107,287 Curran Feb. 8, 1938 2,242,106 Buckman May 13, 1941 2,262,926 Edgar et a1 Nov. 18, 1941 2,355,591 Flaxman Aug. 8, 1944 2,483,618 Skinner July 9, 1946 2,431,792 Datesh et al Dec. 2, 1947 2,556,173 Ebel June 2, *1951 FOREIGN PATENTS Number Country Date 375,724 Great Britain June 30, 1932 OTHER REFERENCES U. S. Pharmacopocia, 9th Decennial Revision, 1916, p. 240.

Handbook of Petroleum, Asphalt and Natural Gas-Cross. Kansas City, Mo. Bull. No. 25 (1931), 414. 

1. A METHOD OF CLEANING AN ENGINE INTERNALLY WHICH COMPRISES INTRODUCING INTO THE CRANKCASE OF THE ENGINE AN AMOUNT OF A CLEANING COMPOSITION AT LEAST EQUAL TO THE LUBRICATING OIL CAPACITY OF THE ENGINE, SAID CLEANING COMPOSITION CONSISTING ESSENTIALLY OF ABOUT 50 TO ABOUT 75 PARTS BY VOLUME OF A HYDROCARBON LUBRICATING OIL HAVING A VISCOSITY RANGING FORM ABOUT 75 SUS AT 100* F. UP TO SAE 30 TO 50 TO 25 PARTS BY VOLUME OF A CRESOLSOAP SOLUTION, SAID SOLUTION COMPRISING ABOUT EQUAL PARTS BY VOLUME OF ORTHO-CRESOL AND OF A POTASSIUM LINSEED OIL SOAP SOLUTION, SAID SOAP SOLUTION HAVING A PH BETWEEN ABOUT 8.5 AND 9.0, IDLING THE ENGINE FOR A PERIOD UP TO ABOUT ONE HOUR AND THEREAFTER DRAINING THE ENGINE. 